Data storage and integrity are important components of information age business operations. Enterprises are increasingly moving toward data protection and disaster recovery strategies to prepare for, and recover from, data loss disasters. While some risks to stored data are physical and tangible (for example, failure of a disk drive, fire, or floods), other dangers are intangible or logical (for example, accidental deletion of files or an attack by a computer virus). Data may be protected from the first category of dangers through physical means, such as remote replication, redundant arrays of inexpensive disks (“RAID”), highly available systems, tape backups, and other mechanisms.
The second category of inadvertent erasure or modification of data is traditionally mitigated through other types of approaches. For example, different solutions may employ file versioning, storage system snapshots, tape backups, or periodic backup to a remote server. Many of these solutions are periodic, meaning that they may be executed once a day or even less frequently. As such, when data needs to be recovered, there is a potential for data loss as great as the amount of data created during the time period between two backups.
Requirements to protect against loss of data, along with various regulatory compliance requirements, are driving a move toward solutions involving Continuous Data Protection (“CDP”). According to the Storage Networking Industry Association's (“SNIA”) CDP Special Interest Group, CDP is a “methodology that continuously captures or tracks data modifications and stores changes independently of the primary data, enabling recovery points from any point in the past. CDP systems may be block, file, or application-based and can provide fine granularities of restorable objects to infinitely variable recovery points.” Such a definition implies three primary aspects to a CDP implementation: the ability to track and capture data; the ability to rollback to any point in the history of the volume; and the ability to store captured data in a location external to the main data.
At the time a CDP system is rolled back, a system operator generally considers the protected data in order to establish a recovery point. Generally, a desired recovery point is very close to the time of a data loss or storage disaster, yet strictly before the loss event so as to ensure data integrity. An operator may wish to perform a recovery review, stepping back and forth to different history points around the time of data loss. In a traditional CDP system, the operator is generally restricted to reviewing in only one direction. This direction is typically the backwards direction and if forward review is desired, the operator may have to recreate the copy of the volume and restart the review process. This procedure does not afford quick and efficient scanning backward and forward through the protected data to find the desired recovery point. As a result, a preferred recovery point for rolling back the volume may not be readily obtainable in a traditional CDP system.
It is with respect to these considerations and others that the disclosure made herein is presented.